Clindamycin Phosphate (Topical) - Mechanism of Action, Indications, Dosage, and Adverse Drug Reactions

Overview:

One percent of acne vulgaris is treated with Clindamycin phosphate topical solution USP. Clindamycin phosphate is found in 10 milligrams per milliliter of solution. Clindamycin is a topical antibiotic that a doctor may prescribe to cure acne. Based on the American Academy of Dermatology, Clindamycin is a first-line treatment for mild-to-moderate acne. It acts by either killing or hindering the growth of certain bacteria. A doctor may prescribe clindamycin to kill Propionibacterium acnes (P. acnes) bacteria that cause pimples. While P. acne bacteria live on the skin normally, these bacteria can infiltrate pores and create irritation, which leads to acne. The FDA approved Clindamycin phosphate foam (Food and Drug Administration) on October 22, 2004, and Clindamycin phosphate gel USP one percent on February 11, 2021, for treating acne vulgaris.

Dosage Forms and Strengths:

• Clindamycin phosphate topical solution contains 10 milligrams (mg) of Clindamycin phosphate. Clindamycin comes in the milliliter (mL) sizes listed below 30 mL, and 60 mL applicator bottles and a carton of 60 single-use pledget applicators are supplied.

• Clindamycin Phosphate topical gel is available in the following sizes: Clindamycin phosphate topical gel contains Clindamycin phosphate, equivalent to 10 mg of Clindamycin per gram in 30 and 60 grams tubes.

• Clindamycin phosphate topical lotion comes in the following sizes and contains Clindamycin phosphate equivalent to 10 mg Clindamycin per milliliter: 60 mL squeeze bottle made of plastic.

For Patients:

How Does the Drug Work?

Clindamycin phosphate comes under an antibiotic class known as Lincosamide or Lincomycin antibiotics and is effective in treating various gram-positive and anaerobic bacterial infections. It acts by preventing bacterial protein synthesis, hence preventing bacterial growth. Clindamycin has a bacteriostatic effect, which means it inhibits bacterial reproduction but does not always kill bacteria.

Dosage:

The concentration of the medicine determines the dosage of the medicine. In addition, the number of dosages taken each day, the duration between doses, and the length of time to take the medicine are all determined by the medical problem for which people are using the medicine.

• As a Foam Form:

Adults and children over 12 need to use it once daily for acne-prone areas. Infants and children under 12, and a doctor must set the dosage.

• As Gel, Solution, and Suspension Forms:

Adults and children over 12 must apply it twice daily on acne-affected areas.

Infants and children must use it under the age of 12, and the dosage has to be advised by a doctor.

Why Is Clindamycin Phosphate (Topical) Prescribed?

Clindamycin topical is applied to treat acne. Clindamycin belongs to the drug class Lincomycin antibiotic. It acts by delaying or preventing the growth of acne-causing bacteria and reducing edema.

How Should Clindamycin Phosphate (Topical) Be Used?

• Clindamycin is available as a foam, gel, solution (liquid), lotion, and pledget (swab) to apply on the skin.

• The foam and gel are typically used once a day. The solution, lotion, pledgets, and most gel types are applied twice daily. Every day, apply topical Clindamycin at the same time.

• Follow the instructions on the prescription label exactly, and ask the doctor or pharmacist if any doubt arises. Use only a little of it or apply it more frequently than the doctor has suggested.

• Clindamycin topical is exclusively for external use. Do not consume the drug; avoid getting it into the nose, eyes, mouth, or vagina. If patients get the medication in the mouth, nose, or eyes, or if their skin is broken, thoroughly clean it with cool water.

• The medication will almost certainly come with instructions for use. Please read and carefully follow the instructions given. If patients have any questions regarding how to use topical Clindamycin, see the doctor or pharmacist.

• Before each usage, thoroughly shake the lotion to ensure the drug is properly mixed.

• The pledgets can only be used once. Only take a pledget from its foil wrapper when patients are prepared to use it. Throw away a pledget as soon as patients have used it once.

• The foam is flammable and may ignite. Stay away from open flames, and do not smoke while applying the foam or for a short time afterward.

What Special Precautions Should Be Taken?

• Before taking topical Clindamycin phosphate, patients should inform the doctor and pharmacist if they are allergic to Clindamycin, Lincomycin, or other medications.

• Inform the pharmacist and doctor about prescription and over-the-counter drugs, vitamins, nutritional supplements, and herbal products that patients use or intend to use. Mention Erythromycin as well as any other drugs applied to the skin. The doctor may need to alter the drug doses or keep a close eye out for negative effects.

• Inform the doctor if patients have or have ever had inflammatory bowel disease (a disorder in which the intestinal lining gets inflamed, irritated, or forms ulcers) or severe diarrhea caused by an antibiotic. Patients may be advised by their doctor not to use topical Clindamycin.

• Patients should also disclose any prior episodes of asthma, eczema (sensitive skin that becomes itchy or irritated easily), or allergies.

• Patients should also notify the doctor whether the patient is pregnant, plan to become pregnant, or are nursing. Patients should contact their doctor if they plan to get pregnant while using topical Clindamycin.

• If patients have dental surgery, inform the doctor or dentist that the patients are using topical Clindamycin.

• Patients should be warned that abrasive or medicated soaps and alcohol-containing skin treatments may aggravate the unfavorable effects of topical Clindamycin. Discuss with the doctor the skincare products patients want to use while receiving topical Clindamycin treatment.

Side Effects:

Clindamycin topical may produce adverse effects. Inform the doctor if patients experience any of the following symptoms that are severe or persistent:

• Dry or peeling skin.

• Skin itchiness or burning.

• Skin redness.

• Oily skin.

• New lesions or pimples.

• Headache.

These adverse effects are typically transient and subside on their own. Some adverse effects can be severe. If patients suffer any of the following symptoms, contact a doctor right away:

• Watery or bloody stools.

• Diarrhea.

• Stomach cramps.

Other negative effects of topical Clindamycin may occur. Contact the doctor if patients have any odd side effects while taking this medicine.

Storage:

Keep the drug in its original container, properly closed, and out of children's reach. It should be kept at ambient temperature, away from sources of extreme heat and moisture (rather than in the bathroom). Do not become ice-cold. Do not expose the Clindamycin foam to temperatures exceeding 120°F (49°C); do not destroy or burn the container.

What Can Be Done in the Event of an Overdose?

Though no overdoses have been identified, symptoms are predicted to be typical of Clindamycin's adverse effect profile and may include

• Abdominal pain.

• Nausea.

• Vomiting.

• Diarrhea.

During clinical studies, a three-year-old child received a daily dosage of 100 mg/kg for five days and experienced only mild gastrointestinal pain and diarrhea.

If there is an overdose or severe symptoms, get emergency medical treatment or call the poison helpline.

For Doctors:

Indications:

Clindamycin Phosphate has been approved as a topical treatment and is indicated for the following clinical conditions:

• For treating mild to moderate acne vulgaris.

• Also used with other oral agents for treating severe acne conditions.

What Are the Pharmacological Aspects?

Pharmacodynamics: No data related to Clindamycin phosphate's pharmacodynamics (topical).

Mechanism of Action: Clindamycin's mechanism of action in treating acne vulgaris is uncertain. Generally, Clindamycin has a bacteriostatic property that inhibits protein synthesis in bacteria. It is evident that by decreasing bacterial growth in acne-prone sites, the occurrence of infection is significantly reduced.

Pharmacokinetics: Following numerous topical applications of Clindamycin Phosphate at a concentration of 10 mg Clindamycin per milliliter (mL) in a mixture of Isopropyl alcohol and water solution, extremely small amounts of Clindamycin (0 to 3 ng/mL (nanogram/milliliters) are detected in the serum. Less than 0.2 percent of the dose is retrieved as Clindamycin in urine. Clindamycin Phosphate is inert in vitro, but fast hydrolysis in vivo transforms it into an active Clindamycin anti-bacterially.

Microbiology:

Clindamycin works by attaching to the RNA of the 50S subunit of the ribosome, which in turn prevents the production of bacterial proteins. Clindamycin possesses bacteriostatic characteristics.

• Antibacterial Properties: Clindamycin is potent against most Propionibacterium acnes isolates in vitro; however, the clinical significance is uncertain.

• Resistance: Clindamycin resistance is most commonly produced by changes in particular nucleotides of the 23S ribosomal RNA. Clindamycin and Lincomycin have 100 percent cross-resistance. Because the attachment sites for these antibacterial agents coincide, there is some cross-resistance among Lincosamides, Macrolides, and Streptogramin B found. Some isolates of Macrolide-resistant bacteria exhibit Clindamycin resistance induced by Macrolides.

Clinical Trials:

Clindamycin Phosphate USP one percent, a topical gel, was more efficacious than the vehicle gel in treating mild-to-moderate acne vulgaris in a 12-week multicenter, randomized, evaluator-blind, vehicle-controlled clinical trial. Patients were given Clindamycin Phosphate USP 1 percent once daily, while the carrier gel was given once daily. The investigator's worldwide assessment revealed a trend favoring Clindamycin Phosphate USP 1 percent over the vehicle. After treatment, the mean reduction in lesion counts was 51 percent inflammatory and 25 percent noninflammatory.

According to a single study, four out of 200 patients developed allergic contact sensitization to Clindamycin Phosphate USP 1 percent topical; however, no signal was discovered in clinical trials under usual usage settings.

Contraindications:

Clindamycin phosphateis not recommended for people with a history of

• Hypersensitivity to Clindamycin or Lincomycin preparations.

• Regional enteritis or ulcerative colitis .

• Antibiotic-associated colitis.

• Associated stomach or intestinal disorders.

Warnings and Precautions:

• The antibiotic is absorbed from the skin surface when Clindamycin is applied topically. Topical and systemic Clindamycin use has been linked to diarrhea, bloody diarrhea, and colitis (including pseudomembranous colitis).

• According to studies, one of the key causes of antibiotic-associated colitis is a toxin(s) produced by Clostridia. Colitis is typically characterized by severe continuous diarrhea and severe stomach cramps, and it may be linked to blood and mucus passage. An endoscopy may indicate pseudomembranous colitis. Diagnosis may be aided by a stool culture for Clostridium difficile and a stool assay for Clostridium difficile toxin.

• When severe diarrhea occurs, the medicine should be stopped. In the case of severe diarrhea, a large intestinal endoscopy should be considered to obtain a clear diagnosis. Opiates and Diphenoxylate with Atropine, which are antiperistaltic drugs, may prolong and/or worsen the illness.

• Clindamycin possesses neuromuscular blocking qualities that may improve the efficacy of other neuromuscular blocking drugs. As a result, it should be used cautiously by those receiving such agents.

• A one percent Clindamycin Phosphate gel was tested for carcinogenicity in mice for two years. Daily doses were three to fifteen times higher than human doses; however, there was no substantial tumor increase. In hairless mice, the gel also reduced the median time to tumor begin.

Drug Interactions:

Clindamycin possesses neuromuscular blocking characteristics that may improve the efficacy of other neuromuscular blocking drugs. Thus, individuals receiving these drugs should proceed with caution. The following drugs are found to cause adverse drug reactions when administered concomitantly:

• Live vaccines like the Cholera vaccine.

• Macrolide antibiotics (Erythromycin).

• Monoclonal antibodies such as Fedratinib.

• Mavacamten (cardiac myosin inhibitors).

• Potent CYP3A Inhibitors (Omaveloxolone).

• Barbiturates (Phenobarbital).

• Primidone (anticonvulsants).

• Anesthetic agents like Atracurium.

• Neuromuscular blockade agents (Metocurin, Tubocurarine).

Specific Considerations:

• Pregnancy: In rat and mouse reproduction experiments, Clindamycin Phosphate, Clindamycin Hydrochloride, and Clindamycin Palmitate Hydrochloride caused no fetal damage. The greatest dose was 432 mg/kg, 84 times higher than the predicted human dose. However, no adequate studies for pregnant women exist, so use only when necessary.

• Lactation and Breastfeeding: No scientific evidence is available to prove the presence of the drug in breast milk and its subsequent effects on the infant’s health. However, the potential risks and benefits should be evaluated before prescribing Clindamycin to breastfeeding mothers.

• Pediatric Use: Its safety and effectiveness in children under 12 have not been proven.

• Geriatric Use: The Clindamycin Phosphate (topical) clinical trial did not include enough individuals aged 65 and up to assess whether older patients respond differently than younger patients.